Implantable neurostimulators have been used or suggested to treat a variety of neurological diseases. In some cases, electrical signals generated by the neurostimulators are applied to regions or structures of the brain via electrodes of leads operably coupled to the stimulator. Often the brain regions or structures that are targeted are very small. As a result, it can be difficult to properly place a lead such that the signal may be applied to the desired target. In addition, placement of leads having large outer diameters into the brain can cause undesired injury to tissue, which in some cases may be the tissue for which therapy is directed.